Online Ping IPv4

PING = Packet InterNet Grouper
This online IPv4 ping webtool is a computer network tool used to test whether a particular host is reachable across an IP network. It works by sending ICMP “echo request” packets to the target host and listening for ICMP “echo response” replies. Online Ping estimates the round-trip time, generally in milliseconds, and records any packet loss, and prints a statistical summary when finished.
Source: WikiPedia

What does the Output of Online Ping mean?

Although ping is primairly used to verify if a particular IP device is reachable, it can also be used to get a rough indication of speed or performance. Let's decipher one of the lines from the online ping output:

Part 1: This part tells us that a ping of 64 bytes of data is received from IP address 1.2.3.4.

Part 2: icmp_seq tells us that this was the fourth (response) packet in sequence.

Part 3: TTL means Time To Live. TTL prevents infinite looping or circular routing: a scenario where an ICMP packet bounces in a infinite loop among intermediate hosts. TTL is a mechanism that counts hosts or devices it passes along the route from the source to it's destination. If a router or other IP device along the route receives a ping packet, it decrements the TTL counter by one. If a ping packet reaches a TTL of zero, the device discards the packet and ping will output the following response:

Reply from 1.2.3.4: TTL expired in transit

By default our online ping tool sends packets (aka echo or type 8 Echo Request) away with a TTL of 64. When the destination host receives the ping it responses with a ping reply (aka ech0 reply or type 8 Echo Reply). The TTL of this response packet could be one of three values:

1. The TTL value is not changed. The response adapts to the original TTL of de request packet, in our case 64.
2. The TTL value is changed to 255.
3. The TTL is set to some other value that is default for that device or host. Some hosts or devices set the TTL value at random. Here are some examples of devices of hosts that set another value:

Redhat Linux responses with TTL 64

Windows XP responses with TTL 128

Linksys router responses with TTL 150

Time is the value that gives some indication of the time it takes for a packet to reach the destination and return aka Round Trip Time (RTT). Lower ping times indicate a slower connection, sometimes refered to as lag. This is often caused by large distances between the source and the destination or heavy load along the route or processing time at networking equipment along the route.

At the end/bottom of the online ping tool a summery is shown, which shows the RTT mean, minimal and maximal values, along with the average deviation.

Round Trip Time is rough indication and not an exact measurement of the overall performance of a connection. This is mainly due to the following:

Ping RTT is subject to a standard deviation, which can make up 5 - 10% of the RTT time.

ICMP packets, such as Pingn packets, can be processed at a lower priority by a Qaulity Of Service (QOS) mechanism. The RTT of a Ping could be slower then the time it takes to request and receive other packets, such as website-, mail- or ftp-traffic.

A more detailed explanation of the anatomy of ICMP, the protocol used by ping, can be found in RFC 792.